Improvement of dielectric strength as microstructural enhancement of XLPE insulation

With the aim of developing XLPE insulation for extra high voltage cable, we investigated the morphology of cross-linked polyethylene. We used a kind of base materials and additives, and controlled curing condition and amount of additives. The effect of addition of additives on morphology of XLPE such as lamellar density, orientation and additive layer were analyzed using TEM analysis and X-ray diffraction test. For evaluation of breakdown strength of XLPE insulation with additives and base materials, the mold-type XLPE specimens were made and evaluated with Weibull plot parameters, and compared with morphological characteristics. We applied this result to model cable and this model cable was found to have superior dielectric strength and morphological characteristics compared with non additive added model cable.